Abstract
In three-dimension acoustic field, it is difficult to control in the whole room using active noise control (ANC) technique. Instead, around-head-control is investigated in this paper. It can make around the head quiet locally with simple equipments. To realize around-head-control, it is necessary for a controller to follow the head movement. However, there is a problem that the control effect during the movement is worse, and the recovery of control effect after the movement is slow by conventional ANC. Against this problem, we propose the new method of improving the adaptation speed when an evaluation point moves. The algorithm can control by interpolating the secondary path of the Filtered-x Algorithm while moving. In the algorithm, the updating size appropriate to each coefficient of the adaptive filter is calculated by using a step size vector. The step size vector is calculated from the coefficient of adaptive filter before updating. The accuracy of interpolation is verified by comparing with the measured secondary path characteristics. The validity of the proposal method is shown by the numerical simulation.
